Recently, an ultrasound system has been used extensively in the medical field due to its non-invasive and non-destructive nature. Modern high-performance ultrasound imaging systems and techniques are commonly used to produce two-dimensional ultrasound images and three-dimensional ultrasound images of internal features of patients.
Generally, the ultrasound system may provide a color Doppler mode, wherein color Doppler images may be obtained. The color Doppler images may visualize velocities and directions of moving objects in a target object by using Doppler shift. The color Doppler images may be represented by various colors, which indicate velocities and directions of moving objects (e.g., heart) or blood flows within blood vessels. In the color Doppler image, for example, the blood flow approaching toward an ultrasound probe may be represented by a red color, while the blood flow moving away from the ultrasound probe may be represented by a blue color. Further, the blood flow of a relatively high speed may be represented by a light color, while the blood flow of a relatively slow speed may be represented by a dark color.
However, when a conventional diagnostic system operates in a color Doppler mode to obtain color Doppler images for a full scan region (e.g., 256 scan lines) in a typical depth (shown in FIG. 1), there is a problem in that the color Doppler images are obtained at a relatively low frame rate of about 1-2 frames/second due to the physical speed limitation of ultrasound signals.